One of the most common male electrical connectors for use in medical applications today consists of a rigid insulating body with one or more conductive contact pins projecting from the body. An electrical cable extending into the body has a conductor which leads to each pin. The pin connector is adapted to be coupled to a female connector having a corresponding number of receptacles arranged and adapted to receive the pins. Usually, each receptacle of the female connector comprises an exteriorly threaded post having an axial passage. A tubular splined contact lines that passage, the contact extending out beyond the post. Screwed onto the post is an interiorly threaded cap having an axial passage which is shaped and arranged so that when the cap is screwed down on the post, its squeezes the splines of that post together. Thus, when the pin of the male connector is received in the receptacle of the female connector and the cap is tightened down, the pin is captured by the splined contacts of the female connector thereby establishing a good electrical and mechanical connection between the two connectors.
A serious problem with male pin connectors of this general type is that when such connectors are disconnected, the contact pins of those connectors are completely exposed. Bearing in mind that the connector may terminate an electrical lead extending to a heart pacing lead or other device implanted in a patient, it is readily apparent that the exposed pins of the male connector constitute a potential hazard to the patient. For example, there have been cases where the pins of the male connector have been inadvertently plugged into an electrical outlet. In other instances, the pin connector has been placed on a conductive surface such that the pins are short circuited causing injury to the person carrying the implanted device connected to that connector. Indeed, enough injuries have been caused by those phenomena that various governments have mandated that the pins of the male pin connector be shielded in such a way as to avoid those problems.